/*
   Copyright (c) 2009 Dave Gamble

   Permission is hereby granted, free of charge, to any person obtaining a copy
   of this software and associated documentation files (the "Software"), to deal
   in the Software without restriction, including without limitation the rights
   to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   copies of the Software, and to permit persons to whom the Software is
   furnished to do so, subject to the following conditions:

   The above copyright notice and this permission notice shall be included in
   all copies or substantial portions of the Software.

   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   THE SOFTWARE.
   */

/* cJSON */
/* JSON parser in C. */

#include <string.h>
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <float.h>
#include <limits.h>
#include <ctype.h>
#include "cJSON.h"

static const char *ep;

const char *cJSON_GetErrorPtr(void) {return ep;}

// 字符串比较，忽略大小写
static int cJSON_strcasecmp(const char *s1,const char *s2)
{
    if (!s1) return (s1==s2)?0:1;if (!s2) return 1;
    for(; tolower(*s1) == tolower(*s2); ++s1, ++s2)	if(*s1 == 0)	return 0;
    return tolower(*(const unsigned char *)s1) - tolower(*(const unsigned char *)s2);
}

// 函数指针，主要是方便修改后，跨平台
static void *(*cJSON_malloc)(size_t sz) = malloc;
static void (*cJSON_free)(void *ptr) = free;

// 复制字符串
static char* cJSON_strdup(const char* str)
{
    size_t len;
    char* copy;

    len = strlen(str) + 1;
    if (!(copy = (char*)cJSON_malloc(len))) return 0;
    memcpy(copy,str,len);
    return copy;
}

// 提供malloc、realloc、free功能
void cJSON_InitHooks(cJSON_Hooks* hooks)
{
    if (!hooks) { /* Reset hooks */
        cJSON_malloc = malloc;
        cJSON_free = free;
        return;
    }

    cJSON_malloc = (hooks->malloc_fn)?hooks->malloc_fn:malloc;
    cJSON_free	 = (hooks->free_fn)?hooks->free_fn:free;
}

/* Internal constructor. */
// 申请内存
static cJSON *cJSON_New_Item(void)
{
    cJSON* node = (cJSON*)cJSON_malloc(sizeof(cJSON));
    if (node) memset(node,0,sizeof(cJSON));
    return node;
}

/* Delete a cJSON structure. */
// 释放内存，递归法，先child，再next
void cJSON_Delete(cJSON *c)
{
    cJSON *next;
    while (c)
    {
        next=c->next;
        if (!(c->type&cJSON_IsReference) && c->child) cJSON_Delete(c->child);
        if (!(c->type&cJSON_IsReference) && c->valuestring) cJSON_free(c->valuestring);
        if (c->string) cJSON_free(c->string);
        cJSON_free(c);
        c=next;
    }
}

/* Parse the input text to generate a number, and populate the result into item. */
/*
 * 将字符串转换为数字，方法很聪明，比如字符串为5.24254e+5
 * 那么转换数字的形式为：
 * 1 * 52425 * pow(10.0,(-5+1*5))
 * 用-5代表小数点后位数
 */
static const char *parse_number(cJSON *item,const char *num)
{
    double n=0,sign=1,scale=0;int subscale=0,signsubscale=1;

    if (*num=='-') sign=-1,num++;	/* Has sign? */
    if (*num=='0') num++;			/* is zero */
    if (*num>='1' && *num<='9')	do	n=(n*10.0)+(*num++ -'0');	while (*num>='0' && *num<='9');	/* Number? */
    if (*num=='.' && num[1]>='0' && num[1]<='9') {num++;		do	n=(n*10.0)+(*num++ -'0'),scale--; while (*num>='0' && *num<='9');}	/* Fractional part? */
    if (*num=='e' || *num=='E')		/* Exponent? */ // 524254 = 5.24254e+5
    {	num++;if (*num=='+') num++;	else if (*num=='-') signsubscale=-1,num++;		/* With sign? */
        while (*num>='0' && *num<='9') subscale=(subscale*10)+(*num++ - '0');	/* Number? */
    }

    n=sign*n*pow(10.0,(scale+subscale*signsubscale));	/* number = +/- number.fraction * 10^+/- exponent */

    item->valuedouble=n;
    item->valueint=(int)n;
    item->type=cJSON_Number;
    return num;
}

/* Render the number nicely from the given item into a string. */
// 打印数字
static char *print_number(cJSON *item)
{
    char *str;
    double d=item->valuedouble;
    // DBL_EPSILON 能表示的有意义的最小正小数，为1E-9
    if (fabs(((double)item->valueint)-d)<=DBL_EPSILON && d<=INT_MAX && d>=INT_MIN)
    {
        str=(char*)cJSON_malloc(21);	/* 2^64+1 can be represented in 21 chars. */
        if (str) sprintf(str,"%d",item->valueint);
    }
    else
    {
        str=(char*)cJSON_malloc(64);	/* This is a nice tradeoff. */
        if (str)
        {
            if (fabs(floor(d)-d)<=DBL_EPSILON && fabs(d)<1.0e60)sprintf(str,"%.0f",d);
            else if (fabs(d)<1.0e-6 || fabs(d)>1.0e9)			sprintf(str,"%e",d);
            else												sprintf(str,"%f",d);
        }
    }
    return str;
}

// 待
static unsigned parse_hex4(const char *str)
{
    unsigned h=0;
    if (*str>='0' && *str<='9') h+=(*str)-'0'; else if (*str>='A' && *str<='F') h+=10+(*str)-'A'; else if (*str>='a' && *str<='f') h+=10+(*str)-'a'; else return 0;
    h=h<<4;str++;
    if (*str>='0' && *str<='9') h+=(*str)-'0'; else if (*str>='A' && *str<='F') h+=10+(*str)-'A'; else if (*str>='a' && *str<='f') h+=10+(*str)-'a'; else return 0;
    h=h<<4;str++;
    if (*str>='0' && *str<='9') h+=(*str)-'0'; else if (*str>='A' && *str<='F') h+=10+(*str)-'A'; else if (*str>='a' && *str<='f') h+=10+(*str)-'a'; else return 0;
    h=h<<4;str++;
    if (*str>='0' && *str<='9') h+=(*str)-'0'; else if (*str>='A' && *str<='F') h+=10+(*str)-'A'; else if (*str>='a' && *str<='f') h+=10+(*str)-'a'; else return 0;
    return h;
}

/* Parse the input text into an unescaped cstring, and populate item. */
static const unsigned char firstByteMark[7] = { 0x00, 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC };
static const char *parse_string(cJSON *item,const char *str)
{
    const char *ptr=str+1;char *ptr2;char *out;int len=0;unsigned uc,uc2;
    if (*str!='\"') {ep=str;return 0;}	/* not a string! */

    while (*ptr!='\"' && *ptr && ++len) if (*ptr++ == '\\') ptr++;	/* Skip escaped quotes. */

    out=(char*)cJSON_malloc(len+1);	/* This is how long we need for the string, roughly. */
    if (!out) return 0;

    ptr=str+1;ptr2=out;
    while (*ptr!='\"' && *ptr)
    {
        if (*ptr!='\\') *ptr2++=*ptr++;
        else
        {
            ptr++;
            switch (*ptr)
            {
                // \b ,退格，将当前位置移到前一列
                case 'b': *ptr2++='\b';	break;
                // \f ,换页，将当前位置移到下页开头
                case 'f': *ptr2++='\f';	break;
                // \n ,换行，将当前位置移动到下页开头
                case 'n': *ptr2++='\n';	break;
                // \r ,回车，将当前位置移到本行开头
                case 'r': *ptr2++='\r';	break;
                // \t ,水平制表，跳到下一个TAB位置
                case 't': *ptr2++='\t';	break;
                case 'u':	 /* transcode utf16 to utf8. */
                          uc=parse_hex4(ptr+1);ptr+=4;	/* get the unicode char. */

                          if ((uc>=0xDC00 && uc<=0xDFFF) || uc==0)	break;	/* check for invalid.	*/

                          if (uc>=0xD800 && uc<=0xDBFF)	/* UTF16 surrogate pairs.	*/
                          {
                              if (ptr[1]!='\\' || ptr[2]!='u')	break;	/* missing second-half of surrogate.	*/
                              uc2=parse_hex4(ptr+3);ptr+=6;
                              if (uc2<0xDC00 || uc2>0xDFFF)		break;	/* invalid second-half of surrogate.	*/
                              uc=0x10000 + (((uc&0x3FF)<<10) | (uc2&0x3FF));
                          }

                          len=4;if (uc<0x80) len=1;else if (uc<0x800) len=2;else if (uc<0x10000) len=3; ptr2+=len;

                          switch (len) {
                              case 4: *--ptr2 =((uc | 0x80) & 0xBF); uc >>= 6;
                              case 3: *--ptr2 =((uc | 0x80) & 0xBF); uc >>= 6;
                              case 2: *--ptr2 =((uc | 0x80) & 0xBF); uc >>= 6;
                              case 1: *--ptr2 =(uc | firstByteMark[len]);
                          }
                          ptr2+=len;
                          break;
                default:  *ptr2++=*ptr; break;
            }
            ptr++;
        }
    }
    *ptr2=0;
    if (*ptr=='\"') ptr++;
    item->valuestring=out;
    item->type=cJSON_String;
    return ptr;
}

/* Render the cstring provided to an escaped version that can be printed. */
// 将字符串变为可转义的形式
static char *print_string_ptr(const char *str)
{
    const char *ptr;char *ptr2,*out;int len=0;unsigned char token;

    if (!str) return cJSON_strdup("");
    ptr=str;
    while ((token=*ptr) && ++len) 
    {
        if (strchr("\"\\\b\f\n\r\t",token)) 
            len++; 
        else if (token<32) 
            len+=5;  
        ptr++;
    }

    out=(char*)cJSON_malloc(len+3);
    if (!out) return 0;

    ptr2=out;ptr=str;
    *ptr2++='\"';
    while (*ptr)
    {
        if ((unsigned char)*ptr>31 && *ptr!='\"' && *ptr!='\\') *ptr2++=*ptr++;
        else
        {
            *ptr2++='\\';
            switch (token=*ptr++)
            {
                case '\\':	*ptr2++='\\';	break;
                case '\"':	*ptr2++='\"';	break;
                case '\b':	*ptr2++='b';	break;
                case '\f':	*ptr2++='f';	break;
                case '\n':	*ptr2++='n';	break;
                case '\r':	*ptr2++='r';	break;
                case '\t':	*ptr2++='t';	break;
                default: sprintf(ptr2,"u%04x",token);ptr2+=5;	break;	/* escape and print */
            }
        }
    }
    *ptr2++='\"';*ptr2++=0;
    return out;
}
/* Invote print_string_ptr (which is useful) on an item. */
static char *print_string(cJSON *item)	{return print_string_ptr(item->valuestring);}

/* Predeclare these prototypes. */
static const char *parse_value(cJSON *item,const char *value);
static char *print_value(cJSON *item,int depth,int fmt);
static const char *parse_array(cJSON *item,const char *value);
static char *print_array(cJSON *item,int depth,int fmt);
static const char *parse_object(cJSON *item,const char *value);
static char *print_object(cJSON *item,int depth,int fmt);

/* Utility to jump whitespace and cr/lf */
// 跳过不可打印字符，ASCII码前32位
static const char *skip(const char *in) {while (in && *in && (unsigned char)*in<=32) in++; return in;}

/* Parse an object - create a new root, and populate. */
cJSON *cJSON_ParseWithOpts(const char *value,const char **return_parse_end,int require_null_terminated)
{
    const char *end=0;
    cJSON *c=cJSON_New_Item();
    ep=0;
    if (!c) return 0;       /* memory fail */

    end=parse_value(c,skip(value));
    if (!end)	{cJSON_Delete(c);return 0;}	/* parse failure. ep is set. */

    /* if we require null-terminated JSON without appended garbage, skip and then check for a null terminator */
    // 以下默认为0
    if (require_null_terminated) {end=skip(end);if (*end) {cJSON_Delete(c);ep=end;return 0;}}
    if (return_parse_end) *return_parse_end=end;
    return c;
}
/* Default options for cJSON_Parse */
cJSON *cJSON_Parse(const char *value) {return cJSON_ParseWithOpts(value,0,0);}

/* Render a cJSON item/entity/structure to text. */
// 格式化打印
char *cJSON_Print(cJSON *item)				{return print_value(item,0,1);}
// 非格式化打印
char *cJSON_PrintUnformatted(cJSON *item)	{return print_value(item,0,0);}

/* Parser core - when encountering text, process appropriately. */
static const char *parse_value(cJSON *item,const char *value)
{
    if (!value)						return 0;	/* Fail on null. */
    // json串为null
    if (!strncmp(value,"null",4))	{ item->type=cJSON_NULL;  return value+4; }
    // json串为false
    if (!strncmp(value,"false",5))	{ item->type=cJSON_False; return value+5; }
    // json串为true
    if (!strncmp(value,"true",4))	{ item->type=cJSON_True; item->valueint=1;	return value+4; }
    // json串以 " 开头，待
    if (*value=='\"')				{ return parse_string(item,value); }
    // 
    if (*value=='-' || (*value>='0' && *value<='9'))	{ return parse_number(item,value); }
    if (*value=='[')				{ return parse_array(item,value); }
    // JSON以 { 开头
    if (*value=='{')				{ return parse_object(item,value); }

    ep=value;return 0;	/* failure. */
}

/* Render a value to text. */
// 转换为字符串格式
static char *print_value(cJSON *item,int depth,int fmt)
{
    char *out=0;
    if (!item) return 0;
    switch ((item->type)&255)
    {
        case cJSON_NULL:	out=cJSON_strdup("null");	break;
        case cJSON_False:	out=cJSON_strdup("false");break;
        case cJSON_True:	out=cJSON_strdup("true"); break;
        case cJSON_Number:	out=print_number(item);break;
        case cJSON_String:	out=print_string(item);break;
        case cJSON_Array:	out=print_array(item,depth,fmt);break;
        case cJSON_Object:	out=print_object(item,depth,fmt);break;
    }
    return out;
}

/* Build an array from input text. */
// 解析数组，原理与parse_object类似
static const char *parse_array(cJSON *item,const char *value)
{
    cJSON *child;
    if (*value!='[')	{ep=value;return 0;}	/* not an array! */

    item->type=cJSON_Array;
    value=skip(value+1);
    if (*value==']') return value+1;	/* empty array. */

    item->child=child=cJSON_New_Item();
    if (!item->child) return 0;		 /* memory fail */
    value=skip(parse_value(child,skip(value)));	/* skip any spacing, get the value. */
    if (!value) return 0;

    while (*value==',')
    {
        cJSON *new_item;
        if (!(new_item=cJSON_New_Item())) return 0; 	/* memory fail */
        child->next=new_item;new_item->prev=child;child=new_item;
        value=skip(parse_value(child,skip(value+1)));
        if (!value) return 0;	/* memory fail */
    }

    if (*value==']') return value+1;	/* end of array */
    ep=value;return 0;	/* malformed. */
}

/* Render an array to text */
static char *print_array(cJSON *item,int depth,int fmt)
{
    char **entries;
    char *out=0,*ptr,*ret;int len=5;
    cJSON *child=item->child;
    int numentries=0,i=0,fail=0;

    /* How many entries in the array? */
    while (child) numentries++,child=child->next;
    /* Explicitly handle numentries==0 */
    if (!numentries)
    {
        out=(char*)cJSON_malloc(3);
        if (out) strcpy(out,"[]");
        return out;
    }
    /* Allocate an array to hold the values for each */
    entries=(char**)cJSON_malloc(numentries*sizeof(char*));
    if (!entries) return 0;
    memset(entries,0,numentries*sizeof(char*));
    /* Retrieve all the results: */
    child=item->child;
    while (child && !fail)
    {
        ret=print_value(child,depth+1,fmt);
        entries[i++]=ret;
        if (ret) len+=strlen(ret)+2+(fmt?1:0); else fail=1;
        child=child->next;
    }

    /* If we didn't fail, try to malloc the output string */
    if (!fail) out=(char*)cJSON_malloc(len);
    /* If that fails, we fail. */
    if (!out) fail=1;

    /* Handle failure. */
    if (fail)
    {
        for (i=0;i<numentries;i++) if (entries[i]) cJSON_free(entries[i]);
        cJSON_free(entries);
        return 0;
    }

    /* Compose the output array. */
    *out='[';
    ptr=out+1;*ptr=0;
    for (i=0;i<numentries;i++)
    {
        strcpy(ptr,entries[i]);ptr+=strlen(entries[i]);
        if (i!=numentries-1) {*ptr++=',';if(fmt)*ptr++=' ';*ptr=0;}
        cJSON_free(entries[i]);
    }
    cJSON_free(entries);
    *ptr++=']';*ptr++=0;
    return out;	
}

/* Build an object from the text. */
// 解析 object
static const char *parse_object(cJSON *item,const char *value)
{
    cJSON *child;
    if (*value!='{')	{ep=value;return 0;}	/* not an object! */

    item->type=cJSON_Object;
    value=skip(value+1);
    if (*value=='}') return value+1;	/* empty array. */

    item->child=child=cJSON_New_Item();
    if (!item->child) return 0;
    // pair 为 string : value ，即先解析string
    value=skip(parse_string(child,skip(value)));
    if (!value) return 0;
    child->string=child->valuestring;child->valuestring=0;
    if (*value!=':') {ep=value;return 0;}	/* fail! */
    // 递归求是string，数字，数组还是object，即 string,[ { 等
    value=skip(parse_value(child,skip(value+1)));	/* skip any spacing, get the value. */
    if (!value) return 0;

    while (*value==',')
    {
        cJSON *new_item;
        if (!(new_item=cJSON_New_Item()))	return 0; /* memory fail */
        child->next=new_item;new_item->prev=child;child=new_item;
        value=skip(parse_string(child,skip(value+1)));
        if (!value) return 0;
        child->string=child->valuestring;child->valuestring=0;
        if (*value!=':') {ep=value;return 0;}	/* fail! */
        value=skip(parse_value(child,skip(value+1)));	/* skip any spacing, get the value. */
        if (!value) return 0;
    }

    if (*value=='}') return value+1;	/* end of array */
    ep=value;return 0;	/* malformed. */
}

/* Render an object to text. */
// 将 Object 格式化为字符串 
static char *print_object(cJSON *item,int depth,int fmt)
{
    char **entries=0,**names=0;
    char *out=0,*ptr,*ret,*str;int len=7,i=0,j;
    cJSON *child=item->child;
    int numentries=0,fail=0;
    /* Count the number of entries. */
    // child 的个数
    while (child) numentries++,child=child->next;
    /* Explicitly handle empty object case */
    // 空object
    if (!numentries)
    {
        out=(char*)cJSON_malloc(fmt?depth+4:3);
        if (!out)	return 0;
        ptr=out;*ptr++='{';
        if (fmt) {*ptr++='\n';for (i=0;i<depth-1;i++) *ptr++='\t';}
        *ptr++='}';*ptr++=0;
        return out;
    }
    /* Allocate space for the names and the objects */
    entries=(char**)cJSON_malloc(numentries*sizeof(char*));
    if (!entries) return 0;
    names=(char**)cJSON_malloc(numentries*sizeof(char*));
    if (!names) {cJSON_free(entries);return 0;}
    memset(entries,0,sizeof(char*)*numentries);
    memset(names,0,sizeof(char*)*numentries);

    /* Collect all the results into our arrays: */
    child=item->child;depth++;if (fmt) len+=depth;
    while (child)
    {
        names[i]=str=print_string_ptr(child->string);
        entries[i++]=ret=print_value(child,depth,fmt);
        if (str && ret) len+=strlen(ret)+strlen(str)+2+(fmt?2+depth:0); else fail=1;
        child=child->next;
    }

    /* Try to allocate the output string */
    if (!fail) out=(char*)cJSON_malloc(len);
    if (!out) fail=1;

    /* Handle failure */
    if (fail)
    {
        for (i=0;i<numentries;i++) {if (names[i]) cJSON_free(names[i]);if (entries[i]) cJSON_free(entries[i]);}
        cJSON_free(names);cJSON_free(entries);
        return 0;
    }

    /* Compose the output: */
    *out='{';ptr=out+1;if (fmt)*ptr++='\n';*ptr=0;
    for (i=0;i<numentries;i++)
    {
        if (fmt) for (j=0;j<depth;j++) *ptr++='\t';
        strcpy(ptr,names[i]);ptr+=strlen(names[i]);
        *ptr++=':';if (fmt) *ptr++='\t';
        strcpy(ptr,entries[i]);ptr+=strlen(entries[i]);
        if (i!=numentries-1) *ptr++=',';
        if (fmt) *ptr++='\n';*ptr=0;
        cJSON_free(names[i]);cJSON_free(entries[i]);
    }

    cJSON_free(names);cJSON_free(entries);
    if (fmt) for (i=0;i<depth-1;i++) *ptr++='\t';
    *ptr++='}';*ptr++=0;
    return out;	
}

/* Get Array size/item / object item. */
int cJSON_GetArraySize(cJSON *array)							
{
    cJSON *c=array->child;
    int i=0;
    while(c)
        i++,c=c->next;
    return i;
}

cJSON *cJSON_GetArrayItem(cJSON *array,int item)				
{
    cJSON *c=array->child;  
    while (c && item>0) 
        item--,c=c->next; 
    return c;
}

cJSON *cJSON_GetObjectItem(cJSON *object,const char *string)	
{
    cJSON *c=object->child; 
    while (c && cJSON_strcasecmp(c->string,string)) 
        c=c->next; 
    return c;
}

/* Utility for array list handling. */
// 连接next prev指针
static void suffix_object(cJSON *prev,cJSON *item) 
{
    prev->next=item;
    item->prev=prev;
}
/* Utility for handling references. */
static cJSON *create_reference(cJSON *item) 
{
    cJSON *ref=cJSON_New_Item();
    if (!ref) 
        return 0;
    memcpy(ref,item,sizeof(cJSON));
    ref->string=0;
    ref->type|=cJSON_IsReference;
    ref->next=ref->prev=0;
    return ref;
}

/* Add item to array/object. */
// 碰到 { 则使用child 指针连接，否则是next prev指针连接 
void cJSON_AddItemToArray(cJSON *array, cJSON *item)						
{
    cJSON *c=array->child;
    if (!item) 
        return; 
    if (!c) 
    {
        array->child=item;
    } 
    else 
    {
        while (c && c->next) 
            c=c->next; 
        suffix_object(c,item);
    }
}

// 向对象里添加条目
void cJSON_AddItemToObject(cJSON *object,const char *string,cJSON *item)	
{
    if (!item) 
        return; 
    if (item->string) 
        cJSON_free(item->string);
    item->string=cJSON_strdup(string);
    cJSON_AddItemToArray(object,item);
}

void cJSON_AddItemReferenceToArray(cJSON *array, cJSON *item)						
{
    cJSON_AddItemToArray(array,create_reference(item));
}

void cJSON_AddItemReferenceToObject(cJSON *object,const char *string,cJSON *item)	
{
    cJSON_AddItemToObject(object,string,create_reference(item));
}

cJSON *cJSON_DetachItemFromArray(cJSON *array,int which)			
{
    cJSON *c=array->child;
    while (c && which>0) 
        c=c->next,which--;
    if (!c) 
        return 0;
    if (c->prev) 
        c->prev->next=c->next;
    if (c->next) 
        c->next->prev=c->prev;
    if (c==array->child) 
        array->child=c->next;
    c->prev=c->next=0;
    return c;
}

void cJSON_DeleteItemFromArray(cJSON *array,int which)			
{
    cJSON_Delete(cJSON_DetachItemFromArray(array,which));
}
    
cJSON *cJSON_DetachItemFromObject(cJSON *object,const char *string) 
{
    int i=0;
    cJSON *c=object->child;
    while (c && cJSON_strcasecmp(c->string,string)) 
        i++,c=c->next;
    if (c) 
        return cJSON_DetachItemFromArray(object,i);
    return 0;
}

void cJSON_DeleteItemFromObject(cJSON *object,const char *string) 
{
    cJSON_Delete(cJSON_DetachItemFromObject(object,string));
}

/* Replace array/object items with new ones. */
void cJSON_ReplaceItemInArray(cJSON *array,int which,cJSON *newitem)		
{
    cJSON *c=array->child;
    while (c && which>0) 
        c=c->next,which--;
    if (!c) 
        return;
    newitem->next=c->next;
    newitem->prev=c->prev;
    if (newitem->next) 
        newitem->next->prev=newitem;
    if (c==array->child) 
        array->child=newitem; 
    else 
        newitem->prev->next=newitem;
    c->next=c->prev=0;
    cJSON_Delete(c);
}
        
void cJSON_ReplaceItemInObject(cJSON *object,const char *string,cJSON *newitem)
{
    int i=0;
    cJSON *c=object->child;
    while(c && cJSON_strcasecmp(c->string,string))
        i++,c=c->next;
    if(c)
    {
        newitem->string=cJSON_strdup(string);
        cJSON_ReplaceItemInArray(object,i,newitem);
    }
}

/* Create basic types: */
// 类型为NULL
cJSON *cJSON_CreateNull(void)					
{
    cJSON *item=cJSON_New_Item();
    if(item)
        item->type=cJSON_NULL;
    return item;
}

// 类型为True
cJSON *cJSON_CreateTrue(void)					
{
    cJSON *item=cJSON_New_Item();
    if(item)
        item->type=cJSON_True;
    return item;
}

// 类型为False
cJSON *cJSON_CreateFalse(void)				
{
    cJSON *item=cJSON_New_Item();
    if(item)
        item->type=cJSON_False;
    return item;
}
        
cJSON *cJSON_CreateBool(int b)					
{
    cJSON *item=cJSON_New_Item();
    if(item)
        item->type=b?cJSON_True:cJSON_False;
    return item;
}
        
// 类型为数字
cJSON *cJSON_CreateNumber(double num)			
{
    cJSON *item=cJSON_New_Item();
    if(item)
    {
        item->type=cJSON_Number;
        item->valuedouble=num;
        item->valueint=(int)num;
    }
    return item;
}
 
// 创建字符串
cJSON *cJSON_CreateString(const char *string)	
{
    cJSON *item=cJSON_New_Item();
    if(item)
    {
        item->type=cJSON_String;
        item->valuestring=cJSON_strdup(string);
    }
    return item;
}

// 创建数组
cJSON *cJSON_CreateArray(void)					
{
    cJSON *item=cJSON_New_Item();
    if(item)item->type=cJSON_Array;
    return item;
}
        
// 创建对象
cJSON *cJSON_CreateObject(void)					
{
    cJSON *item=cJSON_New_Item();
    if(item)
        item->type=cJSON_Object;
    return item;
}

/* Create Arrays: */
// 创建int类型数组
cJSON *cJSON_CreateIntArray(const int *numbers,int count)		
{
    int i;
    cJSON *n=0,*p=0,*a=cJSON_CreateArray();
    for(i=0;a && i<count;i++)
    {
        n=cJSON_CreateNumber(numbers[i]);
        if(!i)
            a->child=n;
        else 
            suffix_object(p,n);
        p=n;
    }
    return a;
}

// 创建float类型数组
cJSON *cJSON_CreateFloatArray(const float *numbers,int count)	
{
    int i;
    cJSON *n=0,*p=0,*a=cJSON_CreateArray();
    for(i=0;a && i<count;i++)
    {
        n=cJSON_CreateNumber(numbers[i]);
        if(!i)
            a->child=n;
        else 
            suffix_object(p,n);
        p=n;
    }
    return a;
}

// 创建double类型数组
cJSON *cJSON_CreateDoubleArray(const double *numbers,int count)	
{
    int i;
    cJSON *n=0,*p=0,*a=cJSON_CreateArray();
    for(i=0;a && i<count;i++)
    {
        n=cJSON_CreateNumber(numbers[i]);
        if(!i)
            a->child=n;
        else 
            suffix_object(p,n);
        p=n;
    }
    return a;
}

// 创建string类型数组
cJSON *cJSON_CreateStringArray(const char **strings,int count)	
{
    int i;
    cJSON *n=0,*p=0,*a=cJSON_CreateArray();
    for(i=0;a && i<count;i++)
    {
        n=cJSON_CreateString(strings[i]);
        if(!i)
            a->child=n;
        else 
            suffix_object(p,n);
        p=n;
    }
    return a;
}

/* Duplication */
cJSON *cJSON_Duplicate(cJSON *item,int recurse)
{
    cJSON *newitem,*cptr,*nptr=0,*newchild;
    /* Bail on bad ptr */
    if (!item) return 0;
    /* Create new item */
    newitem=cJSON_New_Item();
    if (!newitem) return 0;
    /* Copy over all vars */
    newitem->type=item->type&(~cJSON_IsReference),newitem->valueint=item->valueint,newitem->valuedouble=item->valuedouble;
    if (item->valuestring)	
    {
        newitem->valuestring=cJSON_strdup(item->valuestring);	
        if (!newitem->valuestring)	
        {
            cJSON_Delete(newitem);
            return 0;
        }
    }
    if (item->string)		
    {
        newitem->string=cJSON_strdup(item->string);			
        if (!newitem->string)		
        {
            cJSON_Delete(newitem);
            return 0;
        }
    }
    /* If non-recursive, then we're done! */
    if (!recurse) 
        return newitem;
    /* Walk the ->next chain for the child. */
    cptr=item->child;
    while (cptr)
    {
        newchild=cJSON_Duplicate(cptr,1);		/* Duplicate (with recurse) each item in the ->next chain */
        if (!newchild) 
        {
            cJSON_Delete(newitem);
            return 0;
        }
        if (nptr)	
        {
            nptr->next=newchild,newchild->prev=nptr;
            nptr=newchild;
        }	/* If newitem->child already set, then crosswire ->prev and ->next and move on */
        else		
        {
            newitem->child=newchild;
            nptr=newchild;
        }					/* Set newitem->child and move to it */
        cptr=cptr->next;
    }
    return newitem;
}

void cJSON_Minify(char *json)
{
    char *into=json;
    while (*json)
    {
        if (*json==' ') json++;
        else if (*json=='\t') json++;	// Whitespace characters.
        else if (*json=='\r') json++;
        else if (*json=='\n') json++;
        else if (*json=='/' && json[1]=='/')  while (*json && *json!='\n') json++;	// double-slash comments, to end of line.
        else if (*json=='/' && json[1]=='*') {while (*json && !(*json=='*' && json[1]=='/')) json++;json+=2;}	// multiline comments.
        else if (*json=='\"'){*into++=*json++;while (*json && *json!='\"'){if (*json=='\\') *into++=*json++;*into++=*json++;}*into++=*json++;} // string literals, which are \" sensitive.
        else *into++=*json++;			// All other characters.
    }
    *into=0;	// and null-terminate.
}
